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This research addresses the numerical simulation of a working fluid, using specialized SolidWorks Flow Simulation Software, analyzing the behavior of a drying air in a flat solar collector with thermal energy storage. In addition, one of the main centers of computational study is the relationship between flow, air temperature at the outlet of the collector and efficiency; This study allows researchers a vision of the principles of the design of these technologies, especially if it focuses on the drying of food. Then, a proposal is made on the requirements to be taken into account for the sizing of collectors based on the requirements of the product to be dried. Among the results obtained, it is established that a correctly designed collector and under a variable air flow, based on the intensity of the irradiation in specific coordinates and location, can reach efficiencies close to 30% with temperatures close to 60 ° C, being ideal for injecting this fluid into a drying chamber, where the food to be dehydrated is available. For the selection of the volume of the material for energy storage, it is recommended to take the melting temperatures as a base, with a constant flow of air, it is normal that within the system, the temperature varies depending on the position, therefore it is recommending the application of materials with different melting temperatures, which are strategically located within the storage tank. [ABSTRACT FROM AUTHOR]

This study presents the fundamental aspects for the preparation of the technological risks map in the ports of Barranquilla, according to the guidelines for Risk Management, ISO 31000 of 2018. Through the development of a vulnerability analysis, threats of anthropogenic origin and, the levels of risks present in the loading, unloading and storage of dangerous goods in the port environments under investigation were studied. Seventy scenarios of potential technological emergencies were evaluated considering their probability of occurrence, the severity of damage for the victims, the environment and the geographic scope of the areas exposed to the threats. The results simulated in the software ALOHA and GNOME, show the most vulnerable scenarios and establish a preliminary diagnosis for the management of technological disaster risk in the city's ports. It was possible to conclude the feasibility of technological risk maps as a tool for the management of disaster risks in port environments and its preponderant role for the design of emergency plans in organizations. [ABSTRACT FROM AUTHOR]

The use of natural clays for the removal of dyes from wastewater, an important part of environmental remediation, is desirable due, not least, to their low cost. Palygorskite (PAL), a rigidstructure clay, is a good candidate for use in the elimination of industrial effluents, based on its exceptional adsorptive properties. Recently, a new palygorskite deposit has been discovered in Cuba and its use in the adsorption of dyes has not yet been explored in detail. In the present study, the use of unmodified natural Cuban palygorskite as a host for dyes was evaluated. Congo red (CR) and methylene blue (MB) were the anionic and cationic dyes tested, respectively, because of their wide use and toxicity to the environment. Several physical-chemical parameters were studied in order to establish the best experimental conditions under which to achieve the greatest dye load per gram of clay. Natural mixtures with different percentages of montmorillonitewere also tested to evaluate their effect on the adsorption of the dyes. The results indicated that at pH values of ~7-9 and an initial dye concentration of 0.1 mg mL-1, the process was efficient. X-ray diffraction (XRD) analysis proved the surface adsorption of both dyes on the clays. The main interactions involved in the clay-dye system were electrostatic forces and H-bonds. Adsorption of CR seemed to be controlled fundamentally by the palygorskite phase. Such results support the use of this natural clay as an efficient host for the removal of MB and CR from wastewater. [ABSTRACT FROM AUTHOR]

BACKGROUND: Malassezia spp is a saprophyte of the skin, related to diverse cutaneous affections, and has been reported a high frequency in patients with immunosuppression. OBJECTIVE: To determine the prevalence of Malassezia spp in individuals with type 2 diabetes mellitus according to glycemic control. MATERIAL AND METHOD: An open, observational, descriptive and cross-sectional study was performed in volunteer patients who participated in the 24th National March of the Patient with Diabetes in Mexico City on October 15, 2016; where preprandial capillary glycemia and glycosylated hemoglobin were taken. We took a scraping of the malar region skin to find Malassezia spp, smears stained with methylene blue. RESULTS: A total of 49 patients with type 2 diabetes mellitus were included; there were a predominance of 31 patients without glycemic control (67%) in comparison with 16 controlled patients (33%). Smears with low yeast (+) were present in 21 (59%) uncontrolled patients and in 7 (41%) controlled patients; smears with a moderate amount of yeast (++) were present in 7 (74%) uncontrolled patients and in 5 (26%) controlled patients; smears with abundant yeasts were present in 7 (63%) uncontrolled patients and in 2 (37%) controlled patients. CONCLUSION: In our study the prevalence of Malassezia spp in patients with type 2 diabetes mellitus was of 100%, with a lower number of yeasts in patients with adequate glycemic control; this can indicate that the possibility of presenting this yeast increases with bad glycemic control and probably denotes the degree of immunosuppression in these patients. [ABSTRACT FROM AUTHOR]

The gut microbiota plays an important role in host health. The ageing process affects this microbial community, and therefore, the use of functional foods to restore the microbiota of elderly constitutes an interesting strategy. To this end, probiotics and prebiotics targeted at correcting the specific microbiota alterations occurring during senescence are needed. We performed an in vitro selection of bifidobacterial strains and prebiotic substrates on the basis of their ability to counterbalance the specific microbiota aberrancies previously identified in the elderly population. Batch cultures of faeces from elderly were carried out adding different strains of Bifidobacterium or prebiotics. The effects of these strains/prebiotics upon gut microbiota were assessed by quantitative PCR and the concentrations of short chain fatty acids determined by gas chromatography-FID/MS. The target-specific selection process applied in this study allowed the preliminary selection of two Bifidobacterium strains and a prebiotic fructooligosaccharide on the basis of their specific properties for the modulation of the microbiota of elders. Overall, this study identifies potentially probiotic strains and prebiotic substrates for the development of functional foods specifically targeted to the senior population. [ABSTRACT FROM AUTHOR]

During the last years, clays have been increasingly explored as hosts for drugs. In the present paper, we have been able to host the non-steroidal anti-inflammatory drug, Tramadol, into the clay Li-fluorohectorite (Li-Fh). We preliminary evaluate its incorporation by means of UV spectroscopy and X ray diffraction. Our results indicate that the clay hosts the drug molecule in its interlayer space. We suggest a set of parameters to guarantee an efficient incorporation process. Future studies will concentrate on the release of the drug from the clay nanofluid. [ABSTRACT FROM AUTHOR]

Clays have shown to be good candidates as drug delivery carriers. In the present paper, the temperature-dependent swelling of smectites was exploited to obtain composites able to release a drug in a controlled way. More specifically, synthetic fluorohectorite-ciprofloxacin composites were prepared, in which the drug molecules were intercalated between the clay layers. The drug-release systems were characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), thermal gravimetric analysis (TGA), ultraviolet spectroscopy (UV) and atomic absorption spectrometry (AAS). The results from the X-ray diffraction allowed confirming the ciprofloxacin incorporation into the interlayer space, and the results from UV spectroscopy indicated that more than 90% of the initial drug was uptaken by the clay. The thermally activated drug release from a colloidal dispersion of nanosized composite particles in both pure water and synthetic gastric juice was evaluated at temperatures from 37 °C (body temperature) to 85 °C. The studies indicated that the clay promotes the slow release of ciprofloxacin, and that the release of drug increases with both time and temperature. The profiles of drug-release from the clay fulfilled the pharmaceutical standards for these systems. As a result, a clay-based Temperature-Controlled Release System (TCRS) with potential biomedical applications has been obtained. [ABSTRACT FROM AUTHOR]

This article discusses research conducted into the chemical-physical characteristics of glycopeptide-clay nanocomposites in medicine. The authors comment on the interactions between clay and organic molecules and examine the effects of pH level, drug concentration, and temperature on these interactions.

In the present work the incorporation of two model drugs, sulfamethoxazole (SMX) and trimethoprim (TMP) on the Li-fluorohectorite (LiFHt), synthetic clay mineral was evaluated. Understanding the interactions established between these two antibiotics – which are complementary forms from the pharmaceutical point of view – and LiFHt, allows to develop new drug delivery formulations with both drugs in the same support. The quantification of both drugs was followed by ultraviolet (UV) spectroscopy. For the interaction clay mineral-drugs, different physical-chemical parameters−pH, drug initial concentration, temperature and interaction time−were studied. The results showed that, for both drugs, the best clay mineral-drug nanocomposites were obtained at acid pH, room temperature during 1 h, and initial drug concentration of 3 mg/mL. The resulting clay mineral-drug nanocomposites were characterized by X-ray diffraction (XRD), infrared (IR) spectroscopy and thermal gravimetry (TG). It was corroborated by XRD that the TMP was truly intercalated into the clay mineral. However, SMX seems to be adsorbed onto the clay mineral surface. For the LiFHt-TMP nanocomposite, IR suggested clay mineral-drug interactions via amine groups of the TMP. No significant changes in the IR spectrum for the LiFHt-SMX were observed. The drug release profiles showed to follow the pharmaceutical standards, and suggested the possibility to design formulations of drug delivery using LiFHt as carrier. [ABSTRACT FROM AUTHOR]

Introduction: Obesity has been related to iron deficiency (ID). Impaired iron absorption due to an inflammatory state, higher requirements and a poor nutrition are been investigated as contributors. Objectives: The aim of this study was to assess the iron dietary intake accordingly to the RDA and iron status in a subpopulation of obese-overweight compared to normoweight pregnant women participants in the PREOBE Study. Methodology: 59 participants were classified accordingly to pre-pregnancy BMI (obese-overweight-BMI a 25 kg/m², n = 14; normoweight-BMI < 25 kg/m²; n = 45). Dietary iron intake was assessed using a food frequency questionnaire at 34-weeks gestation. Iron supplements use during pregnancy was reported quarterly. Maternal and umbilical cord blood samples were collected at 24'", 34m week and at delivery for iron status assessment. Iron, transferrin and ferritin levels were obtained using the Cobas System Analyzer (Roche Diagnostics, Switzerland). Statistical analysis was performed using IBM-SPSS V20.0. Results: 63% of obese-overweight and 87% of normoweight had a total daily iron intake, from food and supplements, below RDA values for pregnant women (27 mg/day) However, non of them achieved the RDA levels with iron intake from diet alone. Obese-overweight women and their babies showed a worse iron profile than controls. There was a significant direct correlation between total iron intake and maternal serum iron and transferrin saturation index. These results suggest that supplement use is important in achieving the RDA for iron during pregnancy and those obese pregnant women and their babies are at a higher risk of iron deficiency. Further investigations including larger population are needed and nutritional guidelines for obese pregnant women could be considered. [ABSTRACT FROM AUTHOR]

Background: Maternal genetics and feeding before and during pregnancy, different maternal metabolic pathologies, as well as nutrient intakes of newborns in their first months of life may be involved in the obesity aetiology and its long-term consequences. The possible role of these and others factors, the mechanisms and the effects on the metabolism, and the development of this disease need further research. Objective: To acquire more knowledge about foetal adipose tissue development and the influence of genetic, dietetic and environmental factors on the risk to suffer from obesity. Methodology: Four study groups have been established with 30 pregnant women in each one: 1) control group; 2) mothers with glucose intolerance/gestational diabetes; 3) women with low weight gain during pregnancy, and 4) women with overweight/obesity at the beginning of the pregnancy. The magnitudes to be studied are: 1) dietary intake; 2) life-style habits; 3) physical activity; 4) anthropometry and body composition; 5) haematological study; 6) biochemical study (lipid and metabolic biomarkers); 7) immune function profile related to nutritional status; 8) psychological profile; 9) genetic biomarkers, and 10) microbiological markers; all of them in relation to the development of the foetal adipose tissue in the first stages of life and the risk of suffering from obesity in the future. Conclusion: This project, coordinated by the Department of Paediatrics of the School of Medicine in the University of Granada, and with the collaboration of well-known and expert research groups, tries to contribute to the knowledge about the obesity aetiology in infancy and its subsequent development in later periods of life. [ABSTRACT FROM AUTHOR]

Background: Maternal genetics and feeding before and during pregnancy, different maternal metabolic pathologies, as well as nutrient intakes of newborns in their first months of life may be involved in the obesity aetiology and its long-term consequences. The possible role of these and others factors, the mechanisms and the effects on the metabolism, and the development of this disease need further research. Objective: To acquire more knowledge about foetal adipose tissue development and the influence of genetic, dietetic and environmental factors on the risk to suffer from obesity. Methodology: Four study groups have been established with 30 pregnant women in each one: 1) control group; 2) mothers with glucose intolerance/gestational diabetes; 3) women with low weight gain during pregnancy, and 4) women with overweight/obesity at the beginning of the pregnancy. The magnitudes to be studied are: 1) dietary intake; 2) life-style habits; 3) physical activity; 4) anthropometry and body composition; 5) haematological study; 6) biochemical study (lipid and metabolic biomarkers); 7) immune function profile related to nutritional status; 8) psychological profile; 9) genetic biomarkers, and 10) microbiological markers; all of them in relation to the development of the foetal adipose tissue in the first stages of life and the risk of suffering from obesity in the future. Conclusion: This project, coordinated by the Department of Paediatrics of the School of Medicine in the University of Granada, and with the collaboration of well-known and expert research groups, tries to contribute to the knowledge about the obesity aetiology in infancy and its subsequent development in later periods of life. [ABSTRACT FROM AUTHOR]

Abstract: Pluripotent hematopoietic cells from adult bone marrow may give rise not only to neurons, oligodendrocytes and astrocytes after transplantation into newborn brains, but also to neural stem cells (NSC). These NSC localize to both the ventricular epithelium and subventricular zone, persist in the transplanted brain, and may generate neurospheres 1 month after transplant, which after in vitro expansion differentiate into the different neural lineages. Furthermore, the bone marrow-derived NSC differentiate in vivo into functional oligodendrocytes and neurons following demyelinating lesions, thus, demonstrating the ability of adult bone marrow progenitors to generate self-renewing, functional neural stem cells, validating this approach as an alternative source of long-lasting neural stem cells with therapeutic implications in neurodegenerative diseases. [Copyright &y& Elsevier]

Presents a method for aging staged eggs of fish. Classification of egg phase into development stages; Biological information on the daily frequency of spawning and egg development rates; Variability of egg ages.

The objective of this study was evaluated the possible health risks associated with the content of heavy metal and microorganisms in the alfalfa (Medicago sativa L.) juice. Thirteen samples from 33 different markets of Quito-Ecuador were purchased f and analyzed the commercial quality (soluble solids pH, titulable acidity, relative density and humidity), heavy metal (lead, cadmium, copper, chromium and nickel) and microorganism (Aerobic mesophiles and parasites). The results showed that the concentration of lead ranged between 1.40 to 2.49 ppm. These exceeded the maximum limits allowed by CODEX. In addition, in most cases cadmium (0.07 ppm) and copper (0.47 ppm) did not exceed the allowable limits, while chromium (traces) and nickel (0.52 ppm) did not have regulations for their respective comparison. On the other hand, the microbial quality of most of the samples of alfalfa juice showed contamination with mesophilic aerobic microorganism (3.50E+03 UFC/g) and parasites (positive). These finding provide valuable information that can funding food safety decisions, and confirm that the vast majority of vegetables available on Quito's markets present a problem in terms of bacteriological hazards and heavy metal. [ABSTRACT FROM AUTHOR]

We investigate the effect of strong meteorological perturbations in early spring on the success of mackerel ( Scomber scombrus) recruitment in the N/NW Iberian area (southern Bay of Biscay) for the period 1999-2008. In 2000, the year of the most pronounced recruitment failure on record, two consecutive multidisciplinary surveys sampled hydrographic conditions and mackerel eggs, larvae and post-larvae over the main mackerel spawning grounds of the north and northwest coast of the Iberian Peninsula. Analysis of egg and larval abundance and birthdates based on the otoliths of mackerel juveniles caught between July and October 2000 showed that there were no survivors from the early spring spawns, indicating a massive loss of early spawning effort. Moreover, the abundance of 1-year-old mackerel estimated from an acoustic survey carried out in 2001 was the lowest observed within the 1999-2008 time series. This low or null survival from the early spawns in 2000 could be due to the meteorological and oceanographic conditions of that spring, in particular two storm events in April after a relatively calm March. The first storm event from the north caused strong local wind in the southern Bay of Biscay but a weak oceanographic response. The second storm event from the southwest was mainly felt west of Galicia and caused a notable increase in shelf currents and a shift of the hydrographical structure along the shelf. Detailed analysis of strong wind pulses in early spring within the historical recruitment record suggests that strong local turbulence generated by high wind speeds and advection of larvae caused by the enhancement of shelf currents can contribute to reduced recruitment. Our observations indicate that, in 2000, both mechanisms were present. [ABSTRACT FROM AUTHOR]

Abstract: Data on the occurrence of sardine (Sardina pilchardus) eggs from 42 national ichthyoplankton surveys along the European Atlantic coast were collated in order to describe the spawning habitat and spawning distribution of sardine in recent decades (1985–2005). A modification of existing spawning habitat characterisation techniques and a newly developed method to compare the probability of egg presence across surveys carried out with different sampling gears were used. Results showed that sardine spawning off the Atlantic European coast is mainly restricted to the shelf area, with the main geographical range being between the Strait of Gibraltar (the southern limit of data available for this analysis) and the middle part of the Armorican shelf (latitude around 47.5° North), and along a temperature range of 12–17°C. Spawning grounds within these limits show a nearly continuous geographical distribution, covering a large proportion of the shelf of the Iberian peninsula and adjacent waters, except for: (1) a persistent gap at the north west corner of the Iberian peninsula, (2) a small secondary break at the Spanish–French border in the inner part of the Bay of Biscay and (3) at the south west corner of the peninsula where there is a narrowing of the shelf width. These discontinuities were used to separate spawning into four nuclei and to describe the changes in spawning distribution in the time series. The relative importance of each nucleus and the degree of separation between adjacent nuclei varies between years, with the exception of the permanent gap at the northwest corner of the Iberian peninsula, which is persistent throughout the time series. Year to year changes in the proportion of the potential spawning habitat in which spawning actually occurred, changing from around 60% before the mid 1990s to around 40% thereafter, and did not show any relationship with spawning stock biomass. Evolution of potential habitat occupation over the Armorican shelf shows larger variability than that observed in the Iberian peninsula, with percentages of occupation ranging from around 30% up to nearly 80% of the shelf in recent years (within the limitations of the relatively sparse data for this region). [Copyright &y& Elsevier]

The effects of gamma rays on the Cuban antimeningococcic BC vaccine properties were studied. These were performed by simulation with different bioburden of microbial pullutants. The isolated spores of the pullutants of non-aseptic areas were used. Its D10 was determined as 2.045 Gy. On that basis, the sterilization dose setting was performed. The quality of the irradiated vaccine was performed according to the Cuban standards: sterility, protein and polysaccharide concentrations, inmunogenicity, per cent of protein adsorption, nonspecific innocuosness. There were observed non negative effects on the vaccine of the radiation process in the dose range of 0-25 Gy. It was also studied the preservation of the properties of the irradiated vaccine, by storing it during one year at 4°C. The results were satisfactory. [ABSTRACT FROM AUTHOR]

Dengue viruses are endemic in most tropical countries and responsible for epidemics involving up to 100 million cases of dengue fever (DF) and approximately 250000 cases of dengue hemorrhagic fever (DHF) annually. Several reports correlate the participation of proinflamatory cytokines as Tumor necrosis factor alpha (TNFα), Interleukin 1(IL-1) and Interleukin 6 (IL-6) to the pathogenesis of dengue. In the present study, we evaluate the possible association between the severity of the disease and the level of TNFα released by blood cells incubated with dengue virus. Thirty individuals with previous Dengue 2 virus secondary infection and two different clinical forms of the disease (15 individuals Dengue fever and 15 Dengue Hemorrhagic Fever) were studied. Blood samples were incubated in vitro with dengue 3 virus. After 20 hours, supernatants were collected and TNFα was detected by ELISA. Nitric oxide (NO) levels were measured by determining nitrite concentration. Levels of TNFα in plasma supernatants increased more than 2.5 in a 78% of samples in presence of dengue virus comparing with the controls. There were not differences between individuals who suffered DF or DHF. NO levels were homogenous to both groups but its synthesis seems to be elicited by the virus in some immune individuals and inhibited in other. Our results show that TNFα participate in the immune response against dengue virus infection, although the role this cytokine may play in the pathogenesis of DHF is not well established. In addition, it is not being clear the role of NO in dengue infection. [ABSTRACT FROM AUTHOR]